NOTE: for BSA B40 and B44 – models with a separate inspection cover in the clutch cover. the x4 threaded bosses potrude inwards and may touch the end of the new rotor supplied. The remedy is to remove a small about of material using a ‘power file’, or similar grinder from the inside of the threaded boss – typically 2mm. – see images above. Kit not suitable for B50 Use JRC EW4